The Selfie Boy

Mahde is a selfie boy. Every day he uploads new picture in facebook. Today, mark zuckerberg barg gifts him n
boosters. Each booster has it’s own power. The power of i-th booster is ai . Using this booster mahde can increase
the number of like of his facebook picture.
Supppose, the number of his picture’s like is X and apply i-th booser to this picture . After this operation this
picture’s like will be X*ai . Several boost operation can be applied in one picture. But Each booster can be used at
most once. And the booster can be used in any order.
Previous day he uploaded two pictures. He marks that the number of like of his first picture is X and second
picture’s like is Y. Now using the gifted boosters he want to make his first picture’s like equal to exactly A , And
second picture’s like equal to exactly B.
Now, you have to find , the minimum number of booster is needed to reach Mahde’s goal.

Input

First line contains five integers X,Y,A,B and n .
Next line contains n integers a1 , a2 , ..., an where ai is the power of the i-th booster.

• 1≤n≤1000
• 1≤X≤A≤1000 000
• 1≤Y≤B≤1000 000
• 2≤ ai ≤1000 000

Output

Print the a single line contions minimum number of booster is needed to reach Mahde’s goal. If it is impossible print -1. If no booster is needed print 0.

Sample

2 1 10 12 5
2 2 3 5 6

3

Here, 2 is multiplied by 5 and 1 is multiplied by 6 & 2. So the answer is 3.